1. Field of the Invention
This invention relates to exercise equipment and is particularly directed to auxiliary weights which may be attached magnetically to exercise equipment to provide temporary variation of the weights employed by such equipment for stressing the muscles of a person using such equipment.
2. Prior Art
Most types of exercise equipment employ weights which are lifted or moved, either directly or by respective mechanisms, to stress the muscles of a person using the equipment and, hence, to aid in maintaining or improving muscle tone and quality. Typically, such weights are found in dumbbells or barbells or in the so-called "machine stack weights". In most gymnasiums or health clubs, the dumbbells and barbells are stored on racks and are available in fixed five pound weight increments, i.e. 5 lb., 10 lb., 15 lb. etc. Similarly, the weights of the machine stack weights are built into the machines and are usually provided in fixed ten pound weight increments. In each case, the weight increments are fixed or "locked"; that is, they cannot be adjusted in any way to alter the weight increments. This is because impracticalities of space, economy or structural design have discouraged manufacturers from providing smaller weight increments. Unfortunately, the biomechanical limitations of many people who exercise predispose them to excessive strain and possible injury when using the previously available equipment. Thus, for a women or lightly built man to progress from a 15 pound pair of dumbbells to a 20 pound pair of dumbbells represents a 33% increase in workload. It would, obviously, be preferable to progress more gradually. However, with the exercise equipment of the prior art, such gradual increase has been possible only with certain very limited types of equipment.
A search in the United States Patent Office has revealed the following references:
______________________________________ U.S. Pat. No. INVENTOR ISSUED ______________________________________ 3,758,109 M. Bender Sep. 11, 1973 4,453,710 E. Plotz June 12, 1984 4,531,728 G. L. Wright July 30, 1985 4,712,793 M. C. Harwick et al Dec. 15, 1987 ______________________________________
Each of the reference patents discloses exercise equipment having auxiliary weights to permit gradual weight increases. Unfortunately, each of the reference devices provides auxiliary weights which are useful only with the specific equipment for which they were designed. This significantly increases the cost of the equipment and yet provides only limited additional utility. To fully equip a gym or health club with such equipment would be prohibitively expensive and still would not permit gradual weight increases for dumbbells, barbells and the like. Thus none of the prior art auxiliary weight systems have been entirely satisfactory.